With summer underway, families are converging upon the panoply of great destinations in Greater Boston. But what should be a major attraction, the Franklin Park Zoo, has long been an underfunded, second-class amenity. Zoo New England, the organization that runs the zoo, does its best with a challenging location and limited resources. But the Franklin Park Zoo still ranks only 96th out of the 194 Boston attractions rated by TripAdvisor, and time and again Beacon Hill budgeters confront an uncomfortable question: How much taxpayer money should the state devote to an institution that is valuable but never quite manages to thrive financially?

The zoo began 101 years ago as a municipal project funded with private philanthropy. In 1908, George Parkman left more than $100 million (in current dollars) to the city for the maintenance of parks, and a chunk of that money went on the zoo. In August 1912, the Globe reported that six “vicious, untrained” bears arrived from Hamburg. The bear pit was one of the early zoo’s big attractions, despite the Globe’s 1913 reporting that “disgruntled” polar bears “persistently refuse the products of civilization.”

For the next two decades, the zoo was free — and a resounding success. On one day in 1923, 25,000 turned out to see the baby elephant, Molly, consume vast quantities of dirt. In the era, writers earnestly suggested that Boston should have the world’s finest zoo.

That didn’t happen. The zoo’s finances faltered during the Great Depression, and the zoo sank into a long decline, which was not stemmed when control moved from the city to the state in 1958. Years later, when Governor Weld turned Franklin Park and the Stone Zoo over to Zoo New England — a private but state-supported entity — he essentially reversed the old model of public control and private funding. In 2009, zoo officials started talking about killing animals and closing when Governor Patrick tried to cut Zoo New England’s state funding from $6.5 million to $2.5 million.

In response to these cutbacks, Zoo New England significantly boosted other revenues, but its resources still fall short. State funding for the organization ended up at $3.5 million, although the zoo’s 2011 IRS records show that it received $5.5 million in total public grants, which is on a par with Chicago’s exceptional Lincoln Park Zoo. But while Zoo New England received $2.4 million in private donations and almost $5 million in membership dues and other revenue, Lincoln Park earned about twice as much from such sources.

The city’s public delights tend to be downtown and in wealthier neighborhoods. Supporting the Franklin Park Zoo evens that out a bit, especially since school groups visit for free. But the most glorious Boston-area institutions, like the Museum of Science and the Museum of Fine Arts, are largely privately funded. As the zoo’s history illustrates, relying on public funding can lead to neglect and decline, and cutting public grants can lead to private revenue-raising.

Massachusetts needs a better way to shore up such a struggling institution. Through the creative use of tax credits, lawmakers could try to make the zoo
a more attractive philanthropic target, not a permanent ward of the state. If the state offered, for example,
a temporary 10 percent tax credit for donations to the zoo, donors would receive not only their normal federal tax deduction, but also a 10 percent reduction in state taxes. Give $100, and reduce your tax liability by $10.

The plan could even be structured in a way that would permanently strengthen Zoo New England’s fund-raising savvy. In exchange for forgoing, say, $500,000 in state grants, the
organization could receive $1 million of tax credits. The zoo could allocate the credits as it sees fit, as long as no one donor receives more than, say, $1,000 in tax credits.

Such a plan would still involve some loss of revenue for the state, but would also push
the zoo and prospective donors towards private funding. With luck, a five-year tax credit program will make the zoo an attractive magnet for more private dollars in the future.

Boston’s important institutions, like the Franklin Park Zoo, ultimately thrive through private contributions, but sometimes the state should lend a hand.

Edward L. Glaeser, a Harvard economist, is director of the Rappaport Institute for Greater Boston.

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